I agree USB can be the most popular way of connecting your PC to PC speakers. There are USB sound cards with 3.5mm audio ports, so using USB is not a big deal. The audio quality is better on USB Creative Sound Blaster external Sound Cards compared to the sound chips on most motherboards.the green 3.5mm headphone/audio jack for mine as well. Though I imagine it won't be too long before its usb.
It would of been nice of Apple to include an USB-C adapter which has both a headphone jack, SD Card slot, and a few USB A Female port on the adapter.On the new MacBook Pro models, every port is now a USB-C port, which is pointless IMO.
If only the technology would be far enough to properly get replaced, I would understand that.
But at this time, too many devices don't support USB-C, meaning Apple has the right to $$$ you out on buying converters.
This is why I'm thankful I bought a MacBook Pro model before this rather risky change happened.